Evaluation of the increased use of partial resection of large vestibular schwanommas: facial nerve outcomes and recurrence/regrowth rates.

OBJECTIVE

To determine whether partial tumor removal in large vestibular schwannoma improves facial nerve outcomes while maintaining a low risk of tumor regrowth/recurrence.

STUDY DESIGN

Retrospective chart review and prospective database.

SETTING

Tertiary neurotologic referral center.

PATIENTS

Four hundred patients with a vestibular schwannoma of 2.5 cm or greater in maximum diameter undergoing translabyrinthine microsurgical resection from 2001 to 2011. There were 325 gross total resections (GTR), 44 near total resections (NTR), and 31 subtotal resections (STR), with an overall mean tumor size of 3.2 cm (standard deviation, 0.7).

INTERVENTION(S): Translabyrinthine surgical tumor resection.

MAIN OUTCOME MEASURES

House-Brackmann (H-B) facial nerve grade postoperatively and at 1 year, tumor regrowth/recurrence (≥2 mm), additional treatment, and complications.

RESULTS

Higher rates of H-B facial nerve Grades I and II were achieved at both the postoperative and 1-year follow-ups in the NTR (78%, 97%) and STR (71%, 96%) groups compared with GTR (53%, 77%) (p ≤ 0.001). Eye treatment, medical or surgical, was required more often in GTR (28.0%) than NTR and STR (8% and 21%, respectively, p ≤ 0.04), with no other differences in complications. The NTR and STR groups had a significantly higher rate of regrowth than GTR resection (21% and 22% versus 3%) (p ≤ 0.001) at average follow-up times of 3.7, 3.7, and 5.1 years, respectively, and need for further treatment occurred at a higher rate, although infrequently, in NTR and STR (2% and 10% versus 0%) (p ≤ 0.001).

CONCLUSION

Near total and subtotal removal in large tumors are viable treatment options to maintain facial nerve function. During the follow-up period examined in this study, there was a low risk of need for further treatment. Longer-term follow-up is needed to better assess the need for retreatment in patients treated with NTR and STR.